Unique user session tracking in adaptive bitrate video delivery

ABSTRACT

An apparatus having a device of a user and a computer is disclosed. The computer may be configured to (i) transfer a manifest to the device in response to a viewing session being opened. The manifest generally has a plurality of modified links to a plurality of bitrates of a video content. Each one of the modified links may include an identifier that is unique to the viewing session. The computer may also be configured to (ii) receive a particular one of the modified links from the device, (iii) log a presence of the viewing session, and (iv) generate a request by removing the identifier from the particular modified link.

This application relates to U.S. Provisional Application No. 61/883,434, filed Sep. 27, 2013, which is hereby incorporated by reference in its entirety.

FIELD OF THE INVENTION

The present invention relates to video distribution generally and, more particularly, to a method and/or architecture for unique user session tracking in adaptive bitrate video delivery.

BACKGROUND OF THE INVENTION

Identification of unique users watching video over the Internet is difficult. Conventional methods to uniquely track viewing sessions include client-side cookies and tracking Internet Protocol source addresses of client devices. However, the client-side cookies are not always supported by the client devices and can be disabled by the users. Tracking the source addresses does not uniquely identify the users where the client devices operate behind a proxy server or network address translation server.

It would be desirable to implement a unique user session tracking in adaptive bitrate video delivery.

SUMMARY OF THE INVENTION

The present invention concerns an apparatus having a device of a user and a computer. The computer may be configured to (i) transfer a manifest to the device in response to a viewing session being opened. The manifest generally has a plurality of modified links to a plurality of bitrates of a video content. Each one of the modified links may include an identifier that is unique to the viewing session. The computer may also be configured to (ii) receive a particular one of the modified links from the device, (iii) log a presence of the viewing session, and (iv) generate a request by removing the identifier from the particular modified link.

The objects, features and advantages of the present invention include providing a unique user session tracking in adaptive bitrate video delivery that may (i) embed a unique identifier in multiple links within a manifest, (ii) remove the unique identifier from a client selected link, (iii) avoid dependencies on client-side cookies, (iv) work where the clients are behind a proxy server or network address translation server and/or (v) work with multi-bitrate video content.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other objects, features and advantages of the present invention will be apparent from the following detailed description and the appended claims and drawings in which:

FIG. 1 is a diagram illustrating a video processing deployment system in accordance with a preferred embodiment of the present invention;

FIG. 2 is a flow diagram of an example method for initializing a viewing session;

FIG. 3 is a flow diagram of an example method for setup of the viewing session;

FIG. 4 is a flow diagram of an example method for servicing the viewing session; and

FIGS. 5A-5B are a diagram of an example viewing session.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Adaptive bitrate video delivered via hypertext transfer protocol (e.g., HTTP) follows a multi-step technique. A variant manifest may be requested via a HTTP command by a client device. The manifest generally contains universal resource locators (e.g., URLs) that point to all available bitrates for a given media asset. A client player may select an appropriate bitrate and request individual media segments or fragments of the media asset for playback via another HTTP command. When the client device receives each segment or fragment, the received content may be displayed to a user. The client device may periodically request the individual bitrate manifest to determine if updated segments are available to be downloaded.

Some embodiments of the present invention allow hosts in one or more networks to uniquely identify viewing sessions by clients to access media content. The networks are generally supported by one or more origin server computers and one or more edge proxy server computers. A unique identifier may be embedded in the URLs of each request for a particular video rendition. The unique identifiers may be generated randomly and/or read from a list of predetermined identifiers.

For each request of the variant manifest, the origin server computer or a corresponding edge server computers generally adds a unique identifier to each of the URLs in a list of available bitrates. Upon receiving a request with a bitrate URL containing a unique identifier, the edge server computers or the origin server computer logs the unique identifier in a database (a local database, an internal database or a remote database) and presents the original content for the requested URL.

In some embodiments, the origin computer or the edge computers may respond to the requested bitrate URL with a modified bitrate manifest. The modified bitrate manifest generally contains segment (or fragment) URLs that incorporate the unique identifier of the viewing session. Each subsequent request for a particular rendition playlist or media segment or fragment may contain the segment URLs as modified by the unique identifier for that viewing session. Upon receiving a request with a segment URL containing the unique identifier, the edge server computers or the origin server computer presents the original content segment for the requested segment URL.

Referring to FIG. 1, a diagram illustrating a video processing deployment system 100 is shown in accordance with a preferred embodiment of the present invention. The system (or apparatus or architecture) 100 may comprise a number of client devices (or circuits) 102 a-102 n, one or more networks 104 a-104 n, a plurality of edge server computers (or slave server computers) 106 a-106 n, one or more video (or content) source devices (or circuits) 108, one or more video deployment networks 110, and an origin server computer (or master server computer) 112.

Player applications may reside on a number of the client devices 102 a-102 n. The devices 102 a-102 n may include computers, televisions, set-top boxes, cellular telephones, tablets, and other mobile devices. The devices 102 a-102 n may be configured to receive content (e.g., video, audio, audio-video, etc.) from the networks 104 a-104 n (e.g, the Internet). The devices 102 a-102 n may be connected to the networks 104 a-104 n using wired (e.g., cable), wireless (e.g., Wi-Fi, satellite, etc.), third generation (e.g., 3G) links, and/or fourth generation (e.g., 4G) links. Communication between the devices 102 a-102 n and the networks 104 a-104 n may be handled by protocols including, but not limited to, hypertext transfer protocol (e.g., HTTP). Streaming technologies such as Pantos from Apple, Inc., Smooth Streaming from Microsoft Corp., HTTP Dynamic Streaming from Adobe or MPEG Dynamic Adaptive Streaming over HTTP (e.g., MPEG DASH) may be used.

The networks 104 a-104 n generally make a plurality of streams available to the devices 102 a-102 n. The streams may originate from the computer 112 and/or from the encoder/packager device 108 via the computer 112. The streams are subsequently broadcast by the computers 106 a-106 n. Some of the streams may be recorded media assets. Other streams may be live events.

The computer 112 may be configured to store content, service the content to the server computers 106 a-106 n and optionally modify bitrate manifests with unique identifiers. The computer 112 may also communicate with a database 114. The database 114 may compile (or store) the information, metrics, alerts, errors and viewing session data generated by the computers 106 a-106 n.

Referring to FIG. 2, a flow diagram of an example method 120 for initializing a viewing session is shown. The method (or process) 120 generally comprises a step (or state) 122, a step (or state) 124, a step (or state) 125, a step (or state) 126, a step (or state) 128, a step (or state) 130, a step (or state) 132, and a step (or state) 134. The method 120 is generally implemented by the system 100.

In the step 122, a client device (e.g., 102 a) may contact a corresponding edge computer (e.g., 106 a). A purpose of the contact may be to begin a viewing session for video content. For example, the client may browse to a web page having video content available through the edge computer 106 a. The device 102 a may send a request in the step 124 to the computer 106 a via the network 104 a for a variant manifest (or playlist) of a video program. In the step 125, the computer 106 a may determine if the request is already buffered in a cache. If the request is not cached, the computer 106 a may send the request for the variant manifest to the computer 112 via the network 110 in the step 126. If the request is cached, the computer method 120 may continue with the step 132 to generate a modified variant manifest.

In the step 128, the computer 112 generally sends the requested variant manifest to the computer 106 a. The computer 106 a may cache the variant manifest in the step 130. In the step 132, the computer 106 a modifies each bitrate URL link in the requested variant manifest. The modifications may be in the form of a unique identifier added into each bitrate URL in the requested variant manifest. The computer 106 a may record that a new viewing session has started when the variant manifest request (or message) is sent to the computer 112 (e.g., step 126) and/or the unique identifier is generated (e.g., step 132). Once the bitrate URL links have been modified, the computer 106 a generally sends the modified variant manifest back to the requesting device 102 a in the step 134.

Referring to FIG. 3, a flow diagram of an example method 160 for setup of the viewing session is shown. The method (or process) 160 generally comprises a step (or state) 162, a step (or state) 164, a step (or state) 166, a step (or state) 168, a step (or state) 170, a step (or state) 172, a step (or state) 174 and a step (or state) 176. The method 160 is generally implemented by the system 100.

In the step 162, the device 102 a may select a particular modified bitrate URL from the modified variant manifest received from the computer 106 a. The selected modified bitrate URL is returned to the computer 106 a. The computer 106 a may remove the unique identifier from the selected bitrate URL, save the unique identifier and log the request in the step 164.

The computer 106 a generally checks a local cache in the step 166 to determine if a bitrate manifest associated with the requested bitrate URL (with or without the unique identifier) is readily available in the cache. If not, the computer 106 a may send the selected normal (unmodified to remove the unique identifier) bitrate URL to the computer 112 in the step 168. The computer 112 generally responses in the step 170 by sending the requested bitrate manifest to the computer 106 a. The computer 106 a may cache the bitrate manifest received from the computer 112 in the step 172. Regardless if the computer 106 a obtained the requested bitrate manifest from the local cache or from the computer 112, the computer 106 a may modify each segment URL (or link) within the bitrate manifest in the step 174 to add the unique identifier saved in the step 164. In the step 176, the computer 106 a may send the modified requested bitrate manifest to the requesting device 102 a.

Each URL (bitrate URLs and segment URLs) generally includes a scheme name, a host name, a path to a resource, an optional query string, and an optional fragment identifier. The host name may be a domain name or an Internet Protocol (e.g., IP) address. The scheme generally explains how to connect, the host name specifies where to connect, and the remaining items generally specify where the desired resource is located. In some embodiments, the modification of each URL may be an addition of the unique identifier (e.g., a string of alphanumeric characters) to the path portion of the URL. Other positions within the URLs may be modified with the unique identifiers to meet the criteria of a particular application.

Referring to FIG. 4, a flow diagram of an example method 180 for servicing the viewing session is shown. The method (or process) 180 generally comprises a step (or state) 182, a step (or state) 184, a step (or state) 186, a step (or state) 187, a step (or state) 188, a step (or state) 190, a step (or state) 192, a step (or state) 194, a step (or state) 196 and a step (or state) 198. The method 180 is generally implemented by the system 100.

In the step 182, the device 102 a may select a particular modified segment URL from the modified bitrate manifest received from the computer 106 a. The selected modified segment URL is subsequently returned to the computer 106 a. The computer 106 a may remove the unique identifier from the selected segment URL in the step 184. The computer 106 a subsequently increments a count for a duration of the unique viewing session in the step 186. The information (including the duration count) may be logged in the database in the step 187. The database may be in any among the computers 106 a-106 n, the computer 112 and/or a stand-alone database (e.g., 114).

The computer 106 a generally checks a local cache in the step 188 to determine if the video content requested by the segment URL (with or without the unique identifier) is readily available in the cache. If not, the computer 106 a may send the selected normal (unmodified to remove the unique identifier) segment URL to the computer 112 in the step 190. The computer 112 generally responses in the step 192 by sending the requested video segment to the computer 106 a. The computer 106 a generally caches the requested video segment received from the computer 112 in the step 194. The computer 106 a may subsequently send the requested video segment to the requesting device 102 a in the step 196.

The computer 106 a may wait in the step 198 for a next modified segment URL from the device 106 a. Once the next modified segment URL has been received, the method 180 generally resumes with the step 182. The viewing session for the device 102 a generally ends when the client 102 a stops making requests (e.g., logs off, a timeout occurs and the like). The computer 106 a may continue waiting for a next request from the client device 102 a or any other client device 102 b-102 n.

Referring to FIGS. 5A and 5B, a diagram of an example viewing session 220 is shown. The session 220 may be implemented by the computer 112, one of the computers 106 a-106 n (e.g., 106 x) and one of the devices 102 a-102 n (e.g., 102 x).

The session 220 generally begins when the device 102 x issues a HTTP GET command (e.g., GET HTTP://SERVER/VIDEO.M3U8) to the computer 106 x. The computer 106 x may relay the HTTP GET command to the computer 112. The computer 112 may respond to the HTTP GET command with an acknowledge command (e.g., HTTP 200 OK).

The requested content in the example is a video program identified in a playlist (e.g., VIDEO.M3U8). The playlist generally contains bitrate links (e.g., URLs) to multiple (e.g., two) versions of the video program, each version having a different bitrate (e.g., a 620400 bandwidth and a 320400 bandwidth). A low bitrate version may be identified by a bitrate URL link VIDEO_LOW.M3U8. A high bitrate version of the video program is generally identified by a bitrate URL link VIDEO_HIGH.M3U8. The computer 112 generally returns the playlist to the requesting computer 106 a.

The computer 106 x (or in some cases the computer 112) may modify the bitrate URL links to the low bitrate version and the high bitrate version of the video program in the playlist by adding the unique identifier (e.g., 9D5DB222386C4AO2 B733A1579BC457DC). The computer 106 x returns the now-modified variant playlist to the client device 102 x. The modified variant playlist may contain a modified bitrate URL for each version of the video content (e.g., VIDEO_LOW_9D5DB222386C4AO2B733A1579BC457DC.M3U8 and VIDEO_HIGH_9D5DB222386C4AO2B733A1579BC457DC.M3U8)

Once the client device 102 x has determined an appropriate bitrate from the variant playlist VIDEO.M3U8, the device 102 x may transmit the selected (and modified) bitrate URL back to the computer 106 x. The computer 106 x generally logs the request to view the video program in the database. The computer 106 x may also optionally log the requested bitrate in the database. The computer 106 x may remove (or strip) the unique identifier from the modified bitrate URL to recreate the original bitrate URL link (e.g., VIDEO_HIGH.M3U8). If the requested bitrate manifest is not cached by the computer 106 x, the computer 106 x may send a request to the computer 112 (e.g., GET HTTP://SERVER/VIDEO_HIGH.M3U8).

The computer 112 responds to the request for the bitrate manifest by sending one or more segment URLs (e.g., VIDO_HIGH0.TS to VIDEO_HIGH3.TS) back to the requesting computer 106 x. The computer 106 x modifies the URLs in the bitrate manifest by incorporating the unique identifier. The modified bitrate manifest is subsequently transferred from the computer 106 x to the client 102 x.

The client 102 x may select a modified segment URL, which is returned to the computer 106 x. The computer 106 x generally logs the request for the segment and checks the local cache for a copy of the requested segment at the requested bitrate. If a cache copy is found, the computer 106 x generally sends the requested segment of the content to the client 102 x. If no cache copy is found, the computer 106 x strips the unique identifier from the requested segment URL and transfers the normal recreated segment URL back to the computer 112.

The computer 112 generally responds to the recreated segment URL by starting a transmission of the requested original video segment to the computer 106 x. The video stream may then be transmitted to the requesting client device 102 x, where the video is displayed.

While the current viewing session is open, the client device 102 x may re-request the same video content at the same video rate by resending one or more modified segment URLs. Since the computer 106 x has already logged the unique identifier for the current viewing session, the computer 106 x may not add the repeat request for the same content to the database, thus maintaining a log of each unique viewing session. If the client device 102 x requests the same video content at a different video rate, the computer 106 x may comply with the request but not log the request as a new entry in the database. The bitrate URL request for the different bitrate still has the same unique identifier as the earlier bitrate URL request. Thus, the computer 106 x may count unique viewing sessions. If the client device 102 x requests a different video content, the computer 106 x may increment the count in the database to record the viewing session of the different content. If the client device 102 x ends the current viewing session and subsequently opens a new viewing session, the computer 106 x may increment the unique viewing session count to record the new viewing session, though the same content at the same bitrate may be requested in both viewing sessions. In some embodiments, for example a lightly-loaded system—such as a corporate video content delivery network, the computer 112 may perform the tracking functions in place of the computers 106 a-106 n.

The functions and structures illustrated in the diagrams of FIGS. 1-5B may be designed, modeled and simulated using one or more of a conventional general purpose processor, digital computer, microprocessor, microcontroller and/or similar computational machines, programmed according to the teachings of the present specification, as will be apparent to those skilled in the relevant art(s). Appropriate software, firmware, coding, routines, instructions, opcodes, microcode, and/or program modules may readily be prepared by skilled programmers based on the teachings of the present disclosure, as will also be apparent to those skilled in the relevant art(s). The software is generally embodied in a medium or several media, for example a non-transitory storage media, and may be executed by one or more of the processors.

While the invention has been particularly shown and described with reference to the preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made without departing from the scope of the invention. 

The invention claimed is:
 1. A system comprising: a device; and a computer configured to: open a viewing session for video content; generate an initial manifest comprising stored identifiers for a plurality of bitrates of said video content for said viewing session; trannsfer a modified manifest, corresponding to the initial manifest, to said device in response to said viewing session being opened, wherein (a) said modified manifest has a plurality of modified links generated by a modification to the stored identifiers and (b) each one of said modified links includes a session identifier that is unique to said viewing session; receive a request for the video content from said device, the request including a particular one of said modified links; log a presence of said viewing session; and modify the request for the video content by removing said session identifier from said particular modified link.
 2. The system according to claim 1, wherein said computer is further configured to transfer said request to a server.
 3. The system according to claim 2, wherein said server is further configured to transfer said video content to said device at one of said bitrates that corresponds to said request.
 4. The system according to claim 1, wherein said computer is further configured to transfer a cache copy of said video content to said device at one of said bitrates that corresponds to said particular modified link.
 5. The system according to claim 1, wherein said modified links are a plurality of universal resource locators each of which includes said identifier.
 6. The system according to claim 5, wherein said identifier forms part of a path portion in each of said universal resource locators.
 7. The system according to claim 1, wherein (1) said computer is further configured to send a manifest request to a server in response to said viewing session being opened and (2) said server is configured to generate said modified links in response to said manifest request.
 8. The system according to claim 1, wherein said computer is configured to generate said modified links.
 9. The system according to claim 1, wherein said computer is further configured to (1)add said identifier to a plurality of additional links in an additional manifest based on said particular modified link, (2) send said additional manifest to said device, (3) receive a selected one of said additional links from said device and (4) transfer a segment of said video content to said device based on said selected additional link.
 10. A method for unique user session tracking in adaptive bitrate video delivery, comprising the steps of: opening a viewing session for video content; generating an initial manifest comprising stored identifiers for a plurality of bitrates of said video content for said viewing session; transferring a modified manifest, corresponding to the initial manifest, from a computer to a device of said user in response to said viewing session being opened, wherein (1) said modified manifest has a plurality of modified links generated by a modification to the stored identifiers and (2) each one of said modified links includes a session identifier that is unique to said viewing session; receiving a request for the video content from said device to said computer, the request including a particular one of said modified links; logging with said computer a presence of said viewing session; and modifying the request for the video content by removing said session identifier from said particular modified link.
 11. The method according to claim 10, further comprising the step of: transferring said request from said computer to a server.
 12. The method according to claim 11, further comprising the step of: transferring said video content from said server to said device at one of said bitrates that corresponds to said request.
 13. The method according to claim 10, further comprising the step of: transferring a cache copy of said video content from said computer to said device at one of said bitrates that corresponds to said particular modified link.
 14. The method according to claim 10, wherein said modified links are a plurality of universal resource locators each of which includes said identifier.
 15. The method according to claim 14, wherein said identifier forms part of a path portion in each of said universal resource locators.
 16. The method according to claim 10, further comprising the steps of: sending a manifest request from said computer to a server in response to said viewing session being opened; and generating said modified links in said server in response to said manifest request.
 17. The method according to claim 16, further comprising the step of: generating said modified links in said computer.
 18. The method according to claim 10 further comprising the steps of: adding said identifier to a plurality of additional links in an additional manifest based on said particular modified link; sending said additional manifest to said device; receiving a selected one of said additional links from said device; and transferring a segment of said video content to said device based on said selected additional link.
 19. A non-transitory computer readable storage medium including instructions stored thereon which, when executed by a processor, cause the processor to: open a viewing session for video content; generate an initial manifest comprising stored identifiers for a plurality of bitrates of said video content for said viewing session; transfer a modified manifest, corresponding to the initial manifest, to a device in response to said viewing session being opened, wherein (1) said modified manifest has a plurality of modified links generated by a modification to the stored identifiers and (2) each one of said modified links includes a session identifier that is unique to said viewing session; receive a request for the video content from the device, the request including a particular one of said modified links; log a presence of said viewing session; and modify the request for the video content by removing said session identifier from said particular modified link. 